What are you all getting for fuel economy fully loaded and on the trail? I am interested in purchasing a G550 but I'm worried that the already low MPG will dip down into single digits one I have it loaded up.
My G isn't very sensitive to load, but is to low speed. If I'm in high range doing 15-75mph I'm seeing 10-12mpg, but if I'm on difficult trail in low range doing 3-6mph, I'm averaging about 3-6mpg.
Mine should be less efficient than most though, it's on portals, and I run 38" tires aired down quite low when on the trail, 5-10psi low, plus it's an AMG so I have the supercharger making it use more gas as well.
Not a G-Wagen, but my LR3 (6,000 lb AWD SUV with a V8) averages 10 mpg on slower sandy trails. From guys doing the TAT on motorcycles, 250 miles is about the max range you need anywhere in the US, which is the middle of Nevada.
I agree on the load factor. The G isnt perturbed by loads as much as aerodynamics and wind drag at speed. A member of our camping crew has a 2012 G550 and he has it kitted out with a Tepui RTT in a front runner roof rack, 2x 5 gal gas cans mounted on the rack, a fridge + camping stuff in the back and 31.5” KO2s on 18” wheels. On highways at 65-70 mph he gets about 13 mpg. Off road in the desert across a blend of sandy, corrugated runs and rock crawls he gets 8-9 mpg.
I think his blended range is about 275 miles with a 25 gal tank. Frankly that amazes me
I personally have a diesel G (so not apples to apples for you) and I get 17 mpg highway and 13 mpg when aggressively rock crawling. The diesel torque characteristics lend a better off-road consumption. But from what I have seen, it doesn’t matter what the load.
I have been aching to get an ORC aux tank which adds about 18 gal and sits nice and low between the frame rails. Haven’t yet pulled the trigger on it yet
If it's range, then absolutely get an auxiliary tank and mount it underneath the truck to the frame rails. I'd love to do that myself but my air compressor, tank, and CTIS solenoids/plumbing are down there.
I've needed my Jerry cans once in southeastern Oregon. I cannot think of many places in NA where you'd ever need more than five to ten gallons of extra fuel to make it to the next fuel station in a modern G. As others have already stated, a V8 G doesn't care how encumbered it is- I get the same mileage daily driving as I do fully loaded, towing a trailer on a long road trip.
@Yarjammer lots places up here in BC where 10 gals could be required if your range is 250-300 miles. I drive a LR Discovery II and routinely carry 5 or 10 gals of spare, but I do tend to go way out in the middle of nowhere. The biggest issues are road closures either via gate, wash out or slide, turning around to back 200km can be exciting if fuel is low.